Weeks after he was laid off, Cisneros won a Mega Millions jackpot worth $266 million.[4] He and his wife became philanthropists, establishing endowments for scholarships to be given to Latino students at GWU and the University of Southern California. They also founded Generation First Degree Pico Rivera, with the goal of ensuring every Latino household in Pico Rivera has at least one college graduate, and the Gilbert and Jacki Cisneros Foundation with an initial investment of $20 million to provide mentorship in education.[3][5][6] After setting up the foundation, Cisneros earned a Master of Arts from Brown University in Urban Education Policy.[1][2]

Since Royce had been seen as vulnerable, the campaign to unseat him attracted 17 challengers by July of 2017.[7] On January 8, 2018, Ed Royce declared that he would not run for re-election,[9] and the newly open seat led many others to declare their candidacy. Ultimately, the nonpartisan blanket primaryelection for the 39th district in 2018 had 17 candidates: 6 Democrats, 7 Republicans, and 4 others. In addition, there were 5 other candidates who had withdrawn their campaigns before the primary.[10] The large number of candidates from both parties led to fears that Democrats could be locked out of the general election. This election attracted national attention as the "weirdest race in the country" after the California Democratic Party and the Democratic Congressional Campaign Committee brokered a truce on negative campaigning between Gil Cisneros and Andy Thorburn, who had each spent $6 million on their respective campaigns.[11]

Fears of a lockout by either party were not realized when Cisneros advanced to the November runoff election, finishing second in the June primary election to Republican Young Kim,[12] with 19.35% of the vote.[13] This election has been listed as a "Toss-up" by the Cook Political Report and Sabato's Crystal Ball.[10]